RH1185AMK Negative Regulator with Adjustable Current Limit DESCRIPTION ABSOLUTE MAXIMUM RATINGS The RH1185AMK is a 3A low dropout regulator with adjustable current limit and remote sense capability. It can be used as a positive regulator with floating input or as a standard negative regulator with grounded input. The output voltage range is 2.5V to 25V, with ±1% accuracy on the internal reference voltage. (Note 1) The RH1185AMK uses a saturation-limited NPN transistor as the pass element. This structure gives the linear dropout characteristics of a FET pass element with significantly less die area. High efficiency is maintained by using special anti-saturation circuitry that adjusts base drive to track load current. The on-resistance is typically 0.25Ω. Accurate current limit is programmed with a single 1/8W external resistor, with a range of zero to three amperes. A second, fixed internal limit circuit prevents destructive currents if the programming current is accidentally overranged. The RH1185AMK has all the protection features of previous LTC regulators, including power limiting and thermal shutdown. BURN-IN CIRCUIT GND 4.02k 3 GND L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. PACKAGE INFORMATION 15V 1 Input Voltage..............................................................35V Input-Output Differential............................................30V FB Voltage....................................................................7V REF Voltage..................................................................7V Output Voltage...........................................................30V Output Reverse Voltage...............................................2V Operating Ambient Temperature Range... –55°C to 125°C Operating Junction Temperature Range Control Section................................... –55°C to 150°C Power Transistor Section.................... –55°C to 175°C Storage Temperature Range.................... –65°C to 150°C Thermal Resistance Junction to Case TO-3 Control Area..............................................1°C/W Power Transistor................................................3°C/W Lead Temperature (Soldering, 10 sec)................... 300°C REF FB VOUT CASE 2 4 1 2k 4 2k RH1185AMK BI FB 2 CASE IS VIN 3 VOUT REF K PACKAGE 4-LEAD TO-3 METAL CAN –15V rh1185amkfa 1 RH1185AMK TABLE 1: ELECTRICAL CHARACTERISTICS (Preirradiation) VIN = 7.4V, VOUT = 5V, IOUT = 1mA, RLIM = 4.02k, unless otherwise noted. PARAMETER AND CONDITIONS MIN Reference Voltage (At FB Pin) Reference Voltage Tolerence (At FB Pin) (Note 2) VIN – VOUT = 5V, VOUT = VREF TA = 25°C TYP MAX SUBGROUP –55°C ≤ TA ≤ 125°C MIN TYP MAX 2.37 –1.0 0.3 SUBGROUP 2.37 1.0 V 1 Reference Voltage Tolerance VIN – VOUT = 1.2V to VIN = 30V, 1mA ≤ IOUT ≤ 3A, PD ≤ 25W (Note 6), VOUT = 5V, TMIN ≤ TJ ≤ TMAX (Note 9) UNITS % –2.5 2.5 2, 3 % Feedback Pin Bias Current, VOUT = VREF 0.7 2 1 2 2, 3 µA Dropout Voltage (Note 3) IOUT = 0.5A, VOUT = 5V IOUT = 3A, VOUT = 5V 0.2 0.67 0.37 1 1 1 0.55 1.4 2, 3 2, 3 V V Load Regulation (Note 7) IOUT = 5mA to 3A, VIN – VOUT = 1.5V to 10V, VOUT = 5V 0.05 0.3 1 0.8 2, 3 % Line Regulation (Note 7) VIN – VOUT = 1V to 20V, VOUT = 5V 0.002 0.01 1 0.03 2, 3 %/V 3.9 4.4 1 1 Minimum Input Votlage (Note 4) IOUT = 1A, VOUT = VREF IOUT = 3A, VOUT = VREF V V Internal Current Limit (See Graph for Guaranteed Curve) (Note 12) 1.5V ≤ VIN – VOUT ≤ 10V VIN – VOUT = 15V VIN – VOUT = 20V VIN – VOUT = 30V 3.3 2 1 0.2 3.6 3 1.7 0.4 4.2 4.2 2.6 1 1 1 1 1 3.1 2 1 0.2 4.4 4.3 3 1.1 2, 3 2, 3 2, 3 2, 3 A A A A External Current Limit (Note 11) RLIM = 5k, VOUT = 1V RLIM = 15k, VOUT = 1V 2.7 0.9 3 1 3.3 1.1 1 1 2.5 0.8 3.5 1.2 2, 3 2, 3 A A 2.5 3.5 1 3.5 2, 3 mA 25 15 1 1 40 25 2, 3 2, 3 mA mA Quiescent Supply Current (Note 5) IOUT = 5mA, VOUT = VREF , 4V ≤ VIN ≤ 25V Supply Current Change With Load VIN – VOUT = VSAT (Note 10) VIN – VOUT ≥ 2V Thermal Regulation VIN – VOUT = 10V, IOUT = 5mA to 2A 0.014 %/W Reference Voltage Temperature Coefficient (Note 8) 0.01 %/°C rh1185amkfa 2 RH1185AMK TABLE 1A: ELECTRICAL CHARACTERISTICS (Postirradiation) PARAMETER AND CONDITONS Reference Voltage Tolerance VIN – VOUT = 5V, VOUT = VREF Reference Voltage Tolerance VIN – VOUT = 1.2V to VIN = 30V, 1mA ≤ IOUT ≤ 3A, PD ≤ 25W (Note 6), VOUT = 5V, TMIN ≤ TJ ≤ TMAX (Note 9) Feedback PIn Bias Current, VOUT = VREF Dropout Voltage (Note 3) IOUT = 0.5A, VOUT = 5V IOUT = 3A, VOUT = 5V Load Regulation (Note 7) IOUT = 5mA to 3A VIN – VOUT = 1.5V to 10V, VOUT = 5V Line Regulation, Absolute Value (Note 7) VIN – VOUT = 1V to 20V, VOUT = 5V Minimum Input Voltage (Note 4) IOUT = 1A, VOUT = VREF IOUT = 3A, VOUT = VREF Internal Current Limit (Note 12) 1.5V ≤ VIN – VOUT ≤ 10V VIN – VOUT = 15V VIN – VOUT = 20V VIN – VOUT = 30V External Current Limit (Note 11) RLIM = 5k RLIM = 15k Quiescent Supply Current IOUT = 5mA, VOUT = VREF , 4V ≤ VIN ≤ 25V Supply Current Change With Load VIN – VOUT = VSAT VIN – VOUT ≥ 2V 10KRAD(Si) MIN MAX 20KRAD(Si) MIN MAX 50KRAD(Si) MIN MAX 100KRAD(Si) MIN MAX 200KRAD(Si) MIN MAX –1.2 1.2 –1.2 1.2 –1.5 1.5 –1.5 1.5 –2 2 % –3 3 –3 3 –3.2 3.2 –3.5 3.5 –4 4 % UNITS 2 2 2.5 3 3 µA 0.4 1 0.4 1 0.4 1 0.425 1.05 0.45 1.1 V V 0.3 0.4 0.5 0.8 1 % 0.01 0.01 0.01 0.02 0.05 %/V 3.9 4.4 3.9 4.4 3.9 4.4 4 4.5 4 4.5 V V 3.3 2 1 0.2 4.3 4.3 2.7 1 3.3 2 1 0.2 4.3 4.3 2.75 1.15 3.3 2 1 0.2 4.4 4.35 2.85 1.3 3.3 2 1 0.2 4.55 4.5 3.1 1.6 3.3 2 1 0.2 4.75 4.7 3.3 2 A A A A 2.7 0.9 3.3 1.1 2.7 0.9 3.4 1.25 2.7 0.9 3.5 1.4 2.7 0.9 3.7 1.6 2.7 0.9 3.9 1.9 A A 3.5 3.5 3.5 3.5 3.5 mA 25 15 27 16 30 18 35 21 45 27 mA/A mA/A Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Reference voltage is guaranteed both at nominal conditions (no load, 25°C) and at worst-case conditions of load, line, power and temperature. Note 3: Dropout voltage is tested by reducing input voltage until the output drops 1% below its nominal value. Tests are done at 0.5A and 3A. The power transistor looks basically like a pure resistance in this range so that minimum differential at any intermediate current can be calculated by interpolation; VDROPOUT = 0.25V + 0.25Ω • IOUT . For load current other than 0.5A and 3.0A, see graph in LT1185 data sheet. Note 4: “Minimum input voltage” is limited by base emitter voltage drive of the power transistor section, not saturation as measured in Note 3. For output voltages below 4V, “minimum input voltage” specification may limit dropout voltage before transistor saturation limitation. Note 5: Supply current is measured on the ground pin, and does not include load current, RLIM, or output divider current. Note 6: The 25W power level is guaranteed for an input-output voltage of 8.3V to 17V. At lower voltages the 3A limit applies, and at higher voltages the internal power limiting may restrict regulator power below 25W. See graph of Internal Current Limit in LT1185 data sheet. Note 7: Line and load regulation are measured on a pulse basis with a pulse width of ≈2ms, to minimize heating. DC regulation will be affected by thermal regulation and temperature coefficient of the reference. See the Applications Information section of LT1185 data sheet for details. Note 8: Guaranteed by design and correlation to other tests, but not tested. Note 9: TJMIN = –55°C for the RH1185AMK. Power transistor area and control circuit area have different maximum junction temperatures. Control area limit is TJMAX = 150°C for the RH1185AMK. Power area limit is 175°C for RH1185AMK. Note 10: VSAT is the maximum specified dropout voltage; 0.25V + 0.25Ω • IOUT . Note 11: Current limit is programmed with a resistor from REF pin to GND pin. The value is 15k • A/I-limit. Note 12: For VIN – VOUT = 1.5V, VIN = 5V and VOUT = 3.5V. For all other current limit tests, VOUT = 1.0V rh1185amkfa 3 RH1185AMK TABLE 2: POST BURN-IN ENDPOINTS AND DELTA LIMITS REQUIREMENTS TA = 25°C PARAMETER AND CONDITIONS Reference Voltage, VREF VIN = 7.4V, VOUT = VREF ENDPOINT LIMITS MIN MAX 2.346 2.394 DELTA LIMITS MIN MAX –0.040 UNITS 0.040 V TABLE 3: ELECTRICAL TEST REQUIREMENTS MIL-STD-883 TEST REQUIREMENTS PDA Test Notes The PDA is specified as 5% based on failures from Group A, Subgroup 1, tests after cooldown as the final electrical test in accordance with method 5004 of MIL-STD-883. The verified failures of Group A, Subgroup 1, after burn-in divided by the total number of devices submitted for burn-in in that lot shall be used to determine the percent for the lot. Linear Technology Corporation reserves the right to test to tighter limits than those given. SUBGROUP Final Electrical Test Requirements (Method 5004) 1*, 2, 3 Group A Test Requirements (Method 5005) 1, 2, 3 Group B and D for Class S, End Point Electrical Parameters (Method 5005) 1, 2, 3 *PDA applies to subgroup 1. See PDA Test Notes. TOTAL DOSE BIAS CIRCUIT 15V 5k 3 1 GND REF FB VOUT 2 4 4k 4k OUT RH1185AMK DOSE CASE IN –15V rh1185amkfa 4 RH1185AMK REVISION HISTORY REV DATE DESCRIPTION PAGE NUMBER A 02/11 Changed title from RH1185MK to RH1185AMK. Revised Description. Removed REF Pin Shutoff Current from Tables 1 and Table 1A Electrical Characteristics. Removed REF Pin Shutoff Current Plot from the Typical Performance Characteristics section. 1-6 1 2, 3 6 rh1185amkfa Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 5 RH1185AMK TYPICAL PERFORMANCE CHARACTERISTICS VREF VIN – VOUT = 5V VOUT = VREF –2.350 FB Pin Bias Current Quiescent Supply Current 3.5 –2.355 VREF (V) –2.365 –2.370 –2.375 –2.380 IOUT = 5mA VIN = 25V VOUT = VREF 3.0 SUPPLY CURRENT (mA) –2.360 2.0 FB BIAS CURRENT (µA) –2.345 2.5 2.0 –2.385 1.5 1.0 0.5 –2.390 –2.395 0 1.5 200 100 50 150 TOTAL DOSE (kRads) 0 50 100 150 TOTAL DOSE (kRads) Line Regulation 50 100 150 TOTAL DOSE (kRads) 200 RH1185AMK G03 Load Regulation 0 VIN – VOUT = 1V TO 20V VOUT = 5V IOUT = 5mA TO 3A VOUT = 5V –0.05 0.005 LOAD REGULATION (%) LINE REGULATION (%/V) 0 RH1185AMK G02 RH1185AMK G01 0.010 0 200 –0.10 0 –0.15 –0.20 –0.005 –0.25 –0.010 0 50 100 150 TOTAL DOSE (kRads) 200 –0.30 0 50 100 150 TOTAL DOSE (kRads) RH1185AMK G04 RH1185AMK G05 External Current Limit Internal Current Limit 5.0 3.5 4.5 RLIM = 5k INTERNAL CURRENT LIMIT (A) EXTERNAL CURRENT LIMIT (A) 4.0 3.0 2.5 2.0 1.5 RLIM = 15k 1.0 0.5 0 200 4.0 VIN – VOUT = 5V 3.5 VIN – VOUT = 10V 3.0 VIN – VOUT = 15V 2.5 VIN – VOUT = 20V 2.0 1.5 1.0 VIN – VOUT = 30V 0.5 0 100 50 150 TOTAL DOSE (kRads) 200 RH1185AMK G06 0 0 100 50 150 TOTAL DOSE (kRads) 200 RH1185AMK G07 rh1185amkfa 6 Linear Technology Corporation ID No. 66-11-1185MK • LT 0211 REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2009